JP2004217198A - Reclining adjuster for seat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reclining adjuster for a seat capable of enhancing the strength of engagement between the locking teeth of the lock plate and the internal teeth using a limited space without increasing the number of component parts. <P>SOLUTION: When a load applied to a seat back is less than a predetermined value, contact between one of the both side edges of the engaging portion 41 of the lock plate 4 and an end face of one of first and second guide members 22 facing the side edge withstands the load. When the load applied to the seat back is greater than the predetermined value, the contact between one side edge of the engaging portion 41 of the lock plate 4 and the end face of one of the first and second guide members 22 facing the side edge and contact between one of first and second shoulder portions 42, 43 and a portion of the other of the first and second guide members withstand the load. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to an improvement in a seat reclining adjuster.

  Conventionally, a seat reclining adjuster interposed between a seat cushion and a seat back includes a first bracket fixed to one of a seat cushion and a seat back tiltably attached to the seat cushion, and a second bracket. , And is interposed between the first bracket and a second bracket that is connected to the first bracket so as to be relatively rotatable around the center of rotation.

  The reclining adjuster is provided with a cam interposed between the first bracket and the second bracket and fixed so as to be able to co-rotate around a support shaft concentric with the rotation center. This cam causes a lock plate provided with locking teeth on its distal end surface to move in the forward and reverse directions in the radial direction between the first and second brackets by forward and reverse rotation of the support shaft. The first bracket is provided with a guide groove having opposing walls extending in the radial direction and parallel to each other, and the locking teeth are moved forward and reverse in the guide groove by the rotation of the cam, so that the locking teeth are guided in the guide groove. To come and go.

  On the other hand, the second bracket has internal teeth formed along an arc locus concentric with the rotation center. As a result, the lock plate protrudes outward from the guide groove by the rotation of the cam, and the locking teeth mesh with the internal teeth, whereby the relative rotation between the first bracket and the second bracket is restricted, and the cam is rotated. When the engagement of the locking teeth with the internal teeth is released by the reverse rotation, the first bracket and the second bracket can relatively rotate.

  Therefore, by attaching the operation rod to the support shaft and rotating the support shaft forward and backward by operating the operation rod, the locking teeth can be meshed with the internal teeth and the tilting position of the seat back can be locked, and The engagement between the locking teeth and the internal teeth can be released to change the tilting position.

  By the way, in the above-mentioned conventional reclining adjuster, there are sliding contact portions at various places such as between the opposing wall surface of the guide groove and the lock plate or between the cam and the lock plate. However, since there is a gap, when a load is applied to the seat back, the locking teeth tilt in the rotation direction, and the engagement strength with the internal teeth is weakened, so that there is an inconvenience that a reliable locking state cannot be obtained.

  In order to solve such inconvenience, it is conceivable to improve the dimensional accuracy of the guide groove and the lock plate, thereby minimizing the gap between the opposing wall of the guide groove and the lock plate. In addition, extremely precise and high-precision metal processing must be performed on the lock plate and the like, which raises a new problem that the processing cost increases.

  Therefore, the applicant of the present application has proposed that when a load is applied to the seat back in a state where the locking teeth mesh with the internal teeth, the movement of the lock plate tilting in the load direction in the guide groove interferes with the groove edge of the deep portion of the guide groove. Has proposed a seat reclining adjuster having a structure in which a locking projection is provided on a lock plate (see, for example, Patent Document 1).

  According to this reclining adjuster, when a load is applied to the seat back, this force is transmitted to the locking teeth via the internal teeth, and a force is generated in the lock plate in a direction in which the load is applied in the guide groove. When the locking projection interferes with the inner edge of the guide groove, the locking projection cancels out and prevents the lock plate from tilting. Therefore, the inconvenience that the engagement state of the locking teeth with the internal teeth is deteriorated due to the inclination of the lock plate is eliminated, and the set tilting posture of the seat back is maintained.

JP-A-2000-342370 (pages 5-6, FIG. 6)

  However, in the reclining adjuster described in Patent Document 1, when a large load exceeding an allowable load is applied to the seat back and the lock plate excessively presses the side wall of the guide groove to increase the surface pressure, the thickness of the side wall of the guide groove is increased. It is considered that the lock plate is greatly inclined due to the displacement, the engagement between the locking teeth of the lock plate and the internal teeth becomes loose, and the lock strength is reduced.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and utilizes the limited space without increasing the number of parts, and uses the locking strength of the locking teeth of the lock plate with the internal teeth. It is an object of the present invention to provide a seat reclining adjuster capable of surely improving the seat reclining.

  In order to achieve the above object, the invention according to claim 1 of the present invention includes a first bracket fixed to a seat cushion, and a second bracket fixed to a seat back that can be tilted with respect to the seat cushion. A cam rotatably mounted between the first and second brackets, and a locking tooth protruding and retracting radially between the first and second brackets in association with the rotation of the cam. The first bracket has first and second guide members formed with a guide groove for guiding the lock plate to protrude and retract, while the second bracket is provided with a guide groove extending from the guide groove. In a reclining adjuster for a seat having internal teeth meshing with locking teeth at a tip end of a lock plate in a protruding state, the lock plate has first shoulder portions on both sides of the meshing portion. One end face of the first and second guide members, having a second shoulder, wherein one of both side edges of the meshing portion and the one side edge are opposed when a load applied to the seat back is equal to or less than a predetermined value. When the load applied to the seat back is equal to or more than a predetermined value, the first and second guides facing one side edge of the meshing portion and the one side edge are opposed to each other. One end face of the member abuts, and one of the first and second shoulders abuts the other part of the first and second guide members to oppose the load. It is characterized by.

  According to a second aspect of the present invention, each of the first and second shoulders of the lock plate has an engagement protrusion, and a recess formed between the engagement protrusion and the meshing portion. Wherein each of the first and second guide members has an engagement protrusion fitted into the recess, and when the load applied to the seat back is equal to or greater than a predetermined value, the first and second guide members of the lock plate are provided. One of the engaging projections of the two shoulders and one of the first and second guide members are in contact with each other.

  Further, in the invention according to claim 3, each of the first and second guide members has a concave portion in which the engaging convex portion of the first and second shoulders is fitted, and a part of the concave portion. A step portion to be formed, and when the load applied to the seat back is equal to or more than a predetermined value, one of the engagement protrusions of the first and second shoulders and the first and second guide members facing each other. The step portion is in contact with the lock plate to prevent the lock plate from sliding inward in the radial direction of the engagement portion.

  According to the present invention, when the load applied to the seat back is equal to or less than the predetermined value, one of the both side edges of the engagement portion of the lock plate and one end surface of the first and second guide members facing the side edge come into contact with each other. When the load applied to the seat back is equal to or greater than a predetermined value, one side edge of the engagement portion of the lock plate and one end surface of the first and second guide members facing the side edge are opposed to each other. Since the load is brought into contact with one of the first and second shoulders and the other part of the first and second guide members against the load, the internal teeth of the locking teeth of the lock plate are formed. And a reclining adjuster capable of withstanding a larger load than the conventional configuration can be provided.

  Further, when the load applied to the seat back is equal to or greater than a predetermined value, one of the engaging projections of the first and second shoulders comes into contact with the opposing step portions of the first and second guide members, and the lock plate has Since the engagement portion is prevented from sliding inward in the radial direction, the engagement between the locking teeth of the lock plate and the internal teeth of the second bracket is not released, and a reliable locked state is maintained. You.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIGS. 1 to 4 show a reclining adjuster according to the present invention, which is attached to both sides of a seat, and is for holding a seat back in a tiltable manner with respect to a seat cushion.

  The reclining adjuster 1 includes: a first bracket 2 fixed to a seat cushion (not shown); a second bracket 3 fixed to a seat back (not shown) so as to face the first bracket 2; A pair of lock plates 4 interposed between the second brackets 2 and 3, a cam 5 for moving the pair of lock plates 4 in a direction of coming and going, and an operation lever for operating the cam 5 to rotate forward and reverse around the axis. 7 and a holding plate 8 for holding the operation lever 7 in a locked state.

  The upper portion of the first bracket 2 is formed in a circular shape, and a fitting hole 21 for fitting the fitting portion 7a with the cam 5 having a part of the operation lever 7 protruding is formed in the center of the upper circular shape. On the left side (left side in FIG. 4, that is, the surface facing the second bracket 3), a pair of guide members 22 in the front-rear direction is pushed up inward in the width direction (left side in FIG. 4). It is swelled. Each guide member 22 is formed in an arc shape centering on the insertion hole 21 and is shaped symmetrically with respect to the insertion hole 21.

Embodiment 1 FIG.
FIG. 5 is a diagram in which the guide member 22 of the first bracket 2 is superimposed on the view of the lock plate 4 and the cam 5 viewed in the direction of the arrow X in FIG. 4, and particularly shows the first embodiment. As shown in FIG. 5, an accommodation space 24 for accommodating the lock plate 4 and the cam 5 is formed between the pair of left and right guide members 22, and guide projections 22 a are formed at upper and lower ends of each guide member 22. I have. A pair of upper and lower guide grooves 25 are formed between the opposing surfaces of the guide protrusions 22a so as to fit a part of each lock plate 4 (an engagement portion 41 described later) in a sliding contact state, and the diameter of each guide protrusion 22a is formed. On the inner side in the direction, an engagement protrusion 22b for engaging with a part of the lock plate 4 is formed as described later.

  As shown in FIG. 4, the second bracket 3 has a lower portion formed in a circular shape and an attachment portion formed in the upper portion. On the left side surface of the second bracket 3, a circular bulging portion 31 is formed by bulging the lower circular portion as a center, and a fitting hole of the first bracket 2 is formed in the center of the circular bulging portion 31. A through-hole 32 is formed opposite to 21.

  On the right side of the circular bulging portion 31 is a mounting concave portion 33, the inner diameter of which is set slightly larger than the radius of curvature of the outer peripheral surfaces of the pair of guide members 22 described above. With the bracket 3 fitted, each guide member 22 is fitted into the mounting recess 33 while its outer peripheral surface is in sliding contact with the inner peripheral surface of the mounting concave 33. Furthermore, on the upper and lower sides of the inner peripheral surface of the mounting recess 33, internal teeth 34 are formed to face each other.

  At the upper edge of the second bracket 3, mounting holes are formed at the front and rear ends, respectively, and the second bracket 3 serves as a holding plate as a holding plate for holding the first bracket 2 so as not to come off from the second bracket 3 through the mounting holes. The third bracket 35 is bolted, and the third bracket 35 is fixed to the seat back. Then, the third bracket 35 is fixed to the second bracket 3 in a state where the first bracket 2 is stacked on the second bracket 3, so that the third bracket 35 allows the first bracket 2 to rotate, and , Thereby preventing the upper part of the first bracket 2 from separating from the second bracket 3.

  Further, mounting holes are formed in the lower edge of the first bracket 2 at the front and rear ends, respectively, and the first bracket 2 is fixed to the seat cushion by being bolted through these mounting holes.

  As shown in FIG. 5, each lock plate 4 has a meshing portion 41 that is vertically movably fitted into the guide groove 25 of the first bracket 2, and first shoulders formed integrally on both sides of the meshing portion 41. 42, a second shoulder 43, and a leg 44 extending toward the first shoulder 42 of the lock plate 4 located on the opposite side from the second shoulder 43. The engaging portion 41 has locking teeth 41a that mesh with the internal teeth 34 of the second bracket 3 formed at the leading edge, and the locking teeth 41a are engaged with the guide member 22 fitted in the mounting recess 33. The relative rotation between the first bracket 2 and the second bracket 3 is restricted by meshing with the internal teeth 34. On the other hand, the leg 44 has a cam 5 whose linear outer edge is in sliding contact with the linear inner edge of the guide member 22 and whose linear inner edge is rotatably accommodated in a space surrounded by the pair of lock plates 4. The shape is set so as to be in sliding contact with the outer peripheral surface of.

  The length of the leg portion 44 is determined by the engagement position where each lock plate 4 accommodated in the accommodation space 24 moves radially outward and the engagement portion 41 engages with the internal teeth 34 of the second bracket 3. It is set such that it can move inward in the direction and move between an engagement disengagement position where the engagement between the engagement portion 41 and the internal teeth 34 of the second bracket 3 is released. More specifically, the distance between the meshing position and the meshing release position is set to be slightly larger than the tooth length of the locking teeth 41a, and the lock plate 4 is moved radially outward from the fitting hole 21. While the locking teeth 41a of the meshing portion 41 mesh with the internal teeth 34, while the lock plate 4 moves toward the fitting hole 21, the meshing of the locking teeth 41a with the internal teeth 34 is released.

  A first engaging projection 42a is formed radially outside of the first shoulder 42 of each lock plate 4 to abut against the engaging projection 22b of the opposing guide member 22. A second engaging projection 42b is formed on the radially inner side of 42 so as to be in contact with the inner peripheral surface of the distal end of the leg 44 of the lock plate 4 located on the opposite side. A concave portion 42c into which the engaging convex portion 22b of the guide member 22 is fitted is formed between the meshing portion 41 and the first engaging convex portion 42a, and the concave portion 42c is formed by the engaging convex portion of the guide member 22. It has a shape complementary to the shape of 22b. Further, a first engaging projection 43a that is in contact with the engaging projection 22b of the opposing guide member 22 is formed on a radially outer side of the second shoulder 43 of each lock plate 4, and the first engagement projection 43a and the first engagement projection 41a are in contact with each other. A first concave portion 43b into which the engaging convex portion 22b of the guide member 22 fits is formed between the engaging convex portion 43a and the first concave portion 43b having the shape of the engaging convex portion 22b of the guide member 22. It has a complementary shape. A first engaging projection 44a is formed on a part of the linear inner edge of the leg portion 44 to be in contact with the cam 5, and the inner peripheral side of the tip of the leg portion 44 has a first locking projection 4a. A second engagement projection 44b that contacts the second engagement projection 42b of the one shoulder 42 is formed.

  The cam 5 is formed in a substantially hexagonal shape, and has three corners facing one of the lock plates 4, the first protrusions of which abut against the inner peripheral inclined surface 42 d of the first shoulder 42 of the lock plate 4. 5 a, a second protrusion 5 b contacting a second engagement protrusion 43 c formed on the inner peripheral surface of the second shoulder 43, and a third contact contacting the first engagement protrusion 44 a of the leg 44. A first convex portion is formed with a convex portion 5c, and similarly contacts the inner peripheral inclined surface 42d of the first shoulder portion 42 of the lock plate 4 at three corners facing the other lock plate 4. 5a, a second convex portion 5b that contacts the second engaging convex portion 43c formed on the inner peripheral surface of the second shoulder portion 43, and a third convex portion that contacts the first engaging convex portion 44a of the leg portion 44. A portion 5c is formed.

  A long hole 5d is formed in the center of the cam 5, and two notches 5e are formed at both ends on the short axis of the long hole 5d. Two pins (not shown) are integrally formed on one surface (the left convex surface in FIG. 4) of the fitting portion 7a of the operating lever 7, and the fitting portion 7a of the operating lever 7 is connected to the first bracket. The cam 5 is connected to the operating lever 7 by fitting the two pins of the fitting portion 7a into the notches 5e of the cam 5 after fitting into the two fitting holes 21.

  The holding plate 8 for holding the operation lever 7 is attached to the first bracket 2 so as to stabilize the mounting state of the operation lever 7 on the first bracket 2. As shown in FIG. 4, the holding plate 8 includes a plate body 81 that presses the operation lever 7, an arc plate 82 projecting outward from an upper edge of the plate body 81, and a lower edge of the plate body 81. And a spring hooking piece 83 projecting from the rear end of the part.

  A spring hook 71 is also provided at an intermediate portion of the operation lever 7, and a coil spring 84 is stretched between the spring hook 71 of the operation lever 7 and the spring hook 83 of the holding plate 8. As a result, the operation lever 7 is urged in the direction of arrow A.

  Also, the third bracket 35 is provided with a spring-hung protrusion 35a protruding rightward in FIG. 4, and is provided between the spring-hook protrusion 35a and the front edge of the arc plate 82 of the holding plate 8. Is provided with a spiral spring 9. Then, the second bracket 3 receives a biasing force in the direction of arrow B via the third bracket 35 by the spiral spring 9, and the seat back is biased via the second bracket 3 so that the seat back is always in a forwardly inclined posture. ing.

The operation of the reclining adjuster according to the present invention having the above configuration will be described below.
In a normal sitting state in which the operating lever 7 is not operated, the operating lever 7 is urged in the direction of arrow A by the elastic force of the coil spring 84, so that the cam 5 connected to the operating lever 7 also moves in the direction of arrow A. Has been energized.

  In this state, as shown in FIG. 5, the first convex portion 5a and the second convex portion 5b of the cam 5 come into contact with the inner peripheral inclined surface 42d and the second engaging convex portion 43c of the lock plate 4, respectively. The second engagement projection 42b formed on the first shoulder 42 of one lock plate 4 and the second engagement projection 44b of the leg 44 of the other lock plate 4 abut against each other, so that the lock plate The lock plate 4 is urged radially outward while the lock plate 4 is held in a predetermined posture. Therefore, the locking teeth 41a project outwardly from the guide grooves 25 and mesh with the internal teeth 34 of the second bracket 3 which are opposed to each other. The tilt angle is maintained at a predetermined position or a predetermined angle.

  In this state, when the grip portion of the operation lever 7 is pulled up against the elastic force of the coil spring 84, the cam 5 rotates in the direction opposite to the arrow A, and the first convex portion 5a of the cam 5 The cam 5 is fitted into the first concave portion 41b formed between the circumferential inclined surface 42d and the second engaging convex portion 43c, and the second convex portion 5b of the cam 5 is located on the inner peripheral side of the second shoulder portion 43 of the lock plate 4. Is fitted in the second concave portion 43d formed in the second portion. Further, since the third convex portion 5c of the cam 5 comes into contact with and presses the first engaging convex portion 44a of the leg portion 44 of the lock plate 4, the engagement portion 41 of the lock plate 4 has a diameter along the guide groove 25. In this direction, the engagement between the locking teeth 41a and the internal teeth 34 of the second bracket 3 is released, and the lock plate 4 moves from the engagement position to the engagement release position. Therefore, the tilting posture (tilt angle) of the seat back with respect to the seat cushion can be set arbitrarily.

  After setting the tilting posture of the seat back with respect to the seat cushion, when the user releases the grip portion of the operation lever 7, the cam 5 rotates in the direction of arrow A by the elastic force of the coil spring 84, and the lock plate 4 moves outward in the radial direction. , The locking teeth 41a mesh with the internal teeth 34 of the second bracket 3 again, and the seat back is held in the newly set tilting posture.

  When a forward load of a predetermined value or less is applied to the seat back in a state where the locking teeth 41a of the lock plate 4 are engaged with the internal teeth 34 of the second bracket 3, the first engagement of the engagement portion 41 of the lock plate 4 is performed. The side edge on the side of the shoulder 42 is pressed by the side edge of the guide groove 25 (the end face of the guide protrusion 22a of the guide member 22) to increase the surface pressure, oppose the load, and suppress the inclination of the lock plate 4. Further, when a forward load equal to or more than a predetermined value is applied to the seat back, and the guide member 22 or the lock plate 4 is deformed and the lock plate 4 starts to tilt, the engagement portion 41 of the lock plate 4 on the first shoulder portion 42 side. The side edge is pressed by the side edge of the guide groove 25 (the end face of the guide protrusion 22 a of the guide member 22) to increase the surface pressure, and the first engagement protrusion formed on the second shoulder 43 of the lock plate 4. 43a is pressed by the engaging projection 22b formed on the guide projection 22a of the guide member 22 to increase the surface pressure, thereby resisting the load and suppressing the inclination of the lock plate 4.

  On the other hand, when a rearward load of a predetermined value or less is applied to the seat back in a state where the locking teeth 41a of the lock plate 4 are engaged with the internal teeth 34 of the second bracket 3, the second engagement of the engagement portion 41 of the lock plate 4 is performed. The side edge on the side of the shoulder 43 is pressed by the side edge of the guide groove 25 (the end face of the guide protrusion 22a of the guide member 22), and the surface pressure increases, resisting the load and suppressing the inclination of the lock plate 4. Further, in a state where the locking teeth 41a of the lock plate 4 mesh with the internal teeth 34 of the second bracket 3, a rearward load of a predetermined value or more is applied to the seat back, and the guide member 22 or the lock plate 4 is deformed. When the lock plate 4 starts to tilt, the side edge of the engagement portion 41 of the lock plate 4 on the side of the second shoulder 43 is pressed against the side edge of the guide groove 25 (the end surface of the guide protrusion 22a of the guide member 22), and the surface pressure is reduced. At the same time, the first engaging protrusion 42a formed on the first shoulder 42 of the lock plate 4 is pressed by the engaging protrusion 22b formed on the guide protrusion 22a of the guide member 22, and the surface pressure increases. Thus, the configuration is such that the inclination of the lock plate 4 is suppressed against the load.

  That is, when the forward or rearward load applied to the seat back is equal to or less than the predetermined value, the load applied to the seat back against the input by the abutment between the engagement portion 41 of the lock plate 4 and the side edge of the guide groove 25 is opposed. If the load applied to the front or rear is greater than or equal to a predetermined value, the load is counteracted by the contact between the engagement portion 41 of the lock plate 4 and the side edge of the guide groove 25, and then the lock plate or a part of the guide member is The guide plate 22 is deformed, and can withstand the load input by the contact between the second shoulder 43 or the first shoulder 42 of the lock plate 4 and the guide projection 22 a of the guide member 22.

Embodiment 2 FIG.
FIG. 6 shows a second embodiment of the reclining adjuster according to the present invention, and its configuration is basically the same as that of the above-described first embodiment, and only the differences will be described below.

  In the first embodiment, the inner edge sliding contact portion of the guide member 22 with respect to the leg portion 44 of the lock plate 4 is formed in a straight line, whereas in the present embodiment, the inner edge portion of the guide member 22 is vertically A first step portion 22c and a second step portion 22d are respectively formed in FIG. 6 (the left guide member in FIG. 6 (in the case of the right guide member, the lower portion is the first step portion 22c and the upper portion is the second step portion 22d). ), A first concave portion 22e for accommodating the first engaging convex portion 42a of the first shoulder portion 42 of the lock plate 4 is formed between the engaging convex portion 22b of the guide member 22 and the first step portion 22c. On the other hand, the first engagement projection 43a of the second shoulder 43 of the other lock plate 4 is accommodated between the other engagement projection 22b of the guide member 22 and the second step 22d. A recess 22f is formed.

  Further, the first engaging projection 42a of the first shoulder 42 and the first engaging projection 43a of the second shoulder 43 are each formed in a substantially semicircular shape, and serve as guides for the leg 44 of the lock plate 4. The member 22 slightly protrudes outward from an extension of the inner edge sliding contact portion.

  Further, in the first embodiment, the inner edge of the leg portion 44 of the lock plate 4 is formed linearly except for the first engaging projection 44a, and has substantially the same width. In the embodiment, the leg 44 has a width from the second concave portion 43d to the first engagement convex portion 44a wider than the width from the first engagement convex portion 44a to the distal end. Does not have the second engaging projection (44b in the first embodiment). Therefore, the outer edge of the second engaging projection 42 b extends substantially parallel to the inner edge of the guide member 22 and is in sliding contact with the inner edge of the tip of the leg 44 of the lock plate 4. Further, the length of the leg portion 44 in the present embodiment is set shorter than in the first embodiment.

  In the present embodiment, the first engagement protrusion of the first shoulder portion 42 of the lock plate 4 is at the engagement release position where the engagement between the engagement portion 41 of the lock plate 4 and the internal teeth 34 of the second bracket 3 is released. When the first engaging projection 43a of the portion 42a and the second shoulder 43 abuts on the first step 22c and the second step 22d of the guide member 22, movement in the radially inward direction is restricted. As described above, the shapes of the first and second step portions 22c and 22d and the first and second concave portions 22e and 22f are set.

  The reclining adjuster according to the second embodiment of the present invention having the above-described configuration has the same operation as that of the first embodiment in a normal sitting state in which the operation lever 7 is not operated, or when the tilting posture of the seat back with respect to the seat cushion is set. In the state where the locking teeth 41a of the lock plate 4 are engaged with the internal teeth 34 of the second bracket 3, only the operation when a load equal to or more than a predetermined value is applied to the seat back is different from that of the first embodiment. The operation at this time will be described with reference to FIGS.

  When a forward load of a predetermined value or less is applied to the seat back in a state where the locking teeth 41a of the lock plate 4 are engaged with the internal teeth 34 of the second bracket 3, the first shoulder of the engagement portion 41 of the lock plate 4 is provided. The side edge on the 42 side is pressed by the side edge of the guide groove 25 (the end face of the guide projection 22a of the guide member 22), and the surface pressure increases, resisting the load and suppressing the inclination of the lock plate 4. Further, when a forward load equal to or more than a predetermined value is applied to the seat back, and the guide member 22 or the lock plate 4 is deformed and the lock plate 4 starts to tilt, the engagement portion 41 of the lock plate 4 on the first shoulder portion 42 side. The side edge is pressed by the side edge of the guide groove 25 (the end face of the guide projection 22a of the guide member 22), and the surface pressure increases, and the first engagement protrusion 43a formed on the second shoulder 43 of the lock plate 4 is formed. Are pressed by the engaging projections 22 b formed on the guide projections 22 a of the guide member 22 to increase the surface pressure, and the first engagement projections formed on the first shoulder 42 of the engagement portion 41 of the lock plate 4. The portion 42a is pressed against the first step portion 22c of the guide member 22, thereby opposing a large load.

  When the first engaging projection 42a of the lock plate 4 is pressed by the first step portion 22c of the guide member 22 in a state where the lock plate 4 is inclined, the engagement portion 41 of the lock plate 4 engages the guide groove 25. Therefore, the engagement between the locking teeth 41a and the internal teeth 34 of the second bracket 3 is not released, and a reliable locked state is maintained. You.

  On the other hand, when a rearward load of a predetermined value or less is applied to the seat back in a state where the locking teeth 41a of the lock plate 4 are engaged with the internal teeth 34 of the second bracket 3, the second engagement of the engagement portion 41 of the lock plate 4 is performed. The side edge on the side of the shoulder 43 is pressed by the side edge of the guide groove 25 (the end face of the guide projection 22a of the guide member 22), and the surface pressure increases, resisting the load and suppressing the inclination of the lock plate 4 (FIG. 7 line E). Further, in a state where the locking teeth 41a of the lock plate 4 mesh with the internal teeth 34 of the second bracket 3, a rearward load of a predetermined value or more is applied to the seat back, and the guide member 22 or the lock plate 4 is deformed. When the lock plate 4 starts to tilt, the side edge of the engagement portion 41 of the lock plate 4 on the side of the second shoulder 43 is pressed against the side edge of the guide groove 25 (the end surface of the guide projection 22a of the guide member 22), and the surface pressure is reduced. As a result, the first engaging protrusion 42 a formed on the first shoulder 42 of the lock plate 4 is pressed by the engaging protrusion 22 b formed on the guide protrusion 22 a of the guide member 22 to increase the surface pressure. The first engagement projection 43a formed on the second shoulder 43 of the engagement portion 41 of the lock plate 4 is pressed against the second step 22d of the guide member 22 to oppose a large load (FIG. 7). Line F).

  When the first engagement projection 43a of the lock plate 4 is pressed by the second step portion 22d of the guide member 22 in a state where the lock plate 4 is inclined, the engagement portion 41 of the lock plate 4 is engaged with the guide groove 25. Therefore, the engagement between the locking teeth 41a and the internal teeth 34 of the second bracket 3 is not released, and a reliable locked state is maintained. You.

  That is, when the forward or rearward load applied to the seat back is equal to or less than the predetermined value, the load applied to the seat back against the input by the abutment between the engagement portion 41 of the lock plate 4 and the side edge of the guide groove 25 is opposed. If the forward or rearward load applied to the lock plate 4 is equal to or greater than a predetermined value, the load is countered by the contact between the engagement portion 41 of the lock plate 4 and the side edge of the guide groove 25, and then the lock plate 4 or the guide member 22 is closed. The portion is deformed, and further resists the load input by the contact between the second shoulder 43 or the first shoulder 42 of the lock plate 4 and the guide protrusion 22a of the guide member 22, and the first portion of the lock plate 4 The engagement projection 42a or the first engagement projection 43a is pressed by the first step 22c or the second step 22d of the guide member 22 so that the engagement portion of the lock plate 4 is engaged. Since the first slide in the radial inward direction is prevented, it is possible to maintain a positive locking condition meshing is ensured between the internal teeth 34 of the locking teeth 41a and the second bracket 3.

It is a perspective view of the reclining adjuster concerning the present invention. It is a front view of the reclining adjuster of FIG. It is a side view of the reclining adjuster of FIG. It is an exploded perspective view of the reclining adjuster of FIG. FIG. 4 is a diagram in which the guide member of the first bracket is superimposed on the view of the lock plate and the cam as viewed from the direction of arrow X, and particularly shows the first embodiment. FIG. 16 is a diagram corresponding to FIG. 5 showing the second embodiment. FIG. 7 is a partially enlarged view of FIG. 6, particularly illustrating a state where a large load is applied to the seat back and the guide member is deformed.

Explanation of reference numerals

1 reclining adjuster, 2 first bracket, 3 second bracket,
4 lock plate, 5 cam, 5a first convex portion, 5b second convex portion,
5c 3rd convex part, 7 operation lever, 7a fitting part, 8 holding plate,
9 spiral spring, 21 insertion hole, 22 guide member, 22a guide protrusion,
22b engaging convex portion, 22c first step portion, 22d second step portion, 22e first concave portion,
22f second concave portion, 24 accommodation space, 25 guide groove, 31 circular bulging portion,
32 through-hole, 33 mounting recess, 34 internal teeth, 35 third bracket,
41 meshing portion, 41a locking tooth, 41b first concave portion, 42 first shoulder portion,
42a first engagement protrusion, 42b second engagement protrusion, 42c recess,
42d inner peripheral inclined surface, 43 second shoulder portion, 43a first engagement convex portion,
43b first concave portion, 43c second engaging convex portion, 43d second concave portion, 44 leg portion,
44a 1st engaging convex part, 44b 2nd engaging convex part, 84 coil spring.

Claims (3)

A first bracket fixed to the seat cushion, a second bracket fixed to the seat back tiltable with respect to the seat cushion, a cam rotatably mounted between the first and second brackets, and the cam And a lock plate having a meshing portion formed with engaging teeth formed between the first and second brackets in the radial direction in association with the rotation of the first bracket. A reclining adjuster for a seat having first and second guide members having guide grooves formed therein for guiding, and wherein the second bracket has internal teeth meshing with locking teeth at a tip end of a lock plate protruding from the guide grooves. ,
The lock plate has a first shoulder portion and a second shoulder portion on both sides of the engagement portion, and when a load applied to the seat back is equal to or less than a predetermined value, one of the two side edges of the engagement portion and the one side edge. When the load applied to the seat back is equal to or greater than a predetermined value while the load applied to the seat back is equal to or greater than a predetermined value, the first and second guide members oppose one end face of the first and second guide members. The one side edge and one end surface of the first and second guide members facing each other abut, and one of the first and second shoulders and a part of the other of the first and second guide members. A seat reclining adjuster characterized in that the seat reclining adjuster is adapted to oppose the load by abutting against the load. Each of the first and second shoulders of the lock plate has an engagement protrusion and a recess formed between the engagement protrusion and the meshing portion, and the first and second shoulders are provided. Each of the guide members has an engagement projection fitted into the recess, and when the load applied to the seat back is equal to or greater than a predetermined value, the engagement projection on one of the first and second shoulders of the lock plate. 2. The seat reclining adjuster according to claim 1, wherein the portion and the engagement protrusion of one of the first and second guide members abut. 3. Each of the first and second guide members has a concave portion in which the engaging convex portion of the first and second shoulders is fitted, and a step portion forming a part of the concave portion. When the load applied to the lock plate is greater than or equal to a predetermined value, one of the engagement protrusions of the first and second shoulders abuts on the opposing step of the first and second guide members, and the lock plate 3. The seat reclining adjuster according to claim 2, wherein the engagement portion is prevented from sliding inward in the radial direction.

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